In the related art, in a Complementary Metal Oxide Semiconductor (CMOS) solid state imaging device, a rolling shutter system has been adopted. In the rolling shutter system, since charge which is accumulated in a photodiode (PD) is read out for each row, a deviation occurs in time of accumulating photoelectric charge. Accordingly, a distortion occurs in a subject when the subject is moved or the like. In order to prevent the distortion in the subject, a global shutter function that performs an exposure at the same time in all pixels, is necessary.
Therefore, the CMOS solid state imaging device that realizes the global shutter function is proposed (for example, see PTL 1 and PTL 2). In a global shutter system, the charge which is accumulated in the photodiode is temporarily transferred to a charge accumulation unit (memory) at the same time in all the pixels, and the charge is sequentially read out for each row from the charge accumulation unit to an Floating Diffusion (FD). Here, there is a problem that a false signal is made when light from an outside enters the charge accumulation unit while sequentially reading out the charge to the FD. Therefore, in the technology which is disclosed in PTL 1 and PTL 2, a surface irradiation type in which a distance between the charge accumulation unit and a light shielding film is short is adopted, and a configuration that the charge accumulation unit is sufficiently shielded from the light, is adopted.
However, in the method which is disclosed in PTL 1 and PTL 2, since the photodiode and the memory are formed on the same flat surface, it is difficult to increase an area of the photodiode, and to refine the pixel.
Therefore, a structure which is made so as to realize an expansion in the area of the photodiode or the refinement of the pixel by laminating the charge accumulation unit and the FD in a depth direction, is proposed (for example, see PTL 3).